Latest developments in goGPS open source positioning software: EGNOS corrections, integer ambiguity resolution by LAMBDA method and multi-constellation support

Abstract

goGPS is a free and open source positioning software package written in MATLAB that processes single--‐frequency observations in either absolute or relative mode [1]. It can use both code and phase observations by geodetic or low--‐cost receivers. goGPS can compute single--‐epoch solutions by weighted least squares adjustment, or apply a Kalman filter on either positions or observations, also by exploiting a dynamic model. The positioning is optionally supported by route constraints (e.g. a railway). Moreover, it is possible to introduce an additional observation extracted from a digital terrain model in order to increase the accuracy in the vertical direction. goGPS is developed collaboratively online, thus users can contribute code and propose new features and tools. During last year the following improvements have been added to the software, partly contributed by users: the possibility to use EGNOS ionospheric, pseudorange and satellite position/clock corrections (also by exploiting the EGNOS Message Server--‐EMS) for absolute positioning, the resolution of integer ambiguities by LAMBDA method in single--‐frequency relative positioning, and multi--‐constellation support including GLONASS, Galileo, BeiDou and QZSS. In this work we present the state of the art of the software and the performance achieved with the latest implemented features.

Full text

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NORTH [m]
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mean GPS+EGNOS
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